The Percutaneous Pedicle Screw Fixation Procedure

Percutaneous pedicle screw fixation is a minimally-invasive surgical technique that allows supplemental fixation to increase the stiffness and enhance the healing potential of the spinal fusion construct. These screws are used to connect adjacent vertebrae in the spine. The screws are placed down a cylinder of bone from the back to the front of the vertebra called the pedicle. Percutaneous screws are placed after an incision in the skin by piercing the muscle and leaving the muscle intact then the screws are connected by rods placed under the muscle and are secured by top-locking caps. These screws are often required when there has been previous laminectomy, slipping of the bones, scoliosis, or in multiple levels of fusion.

A percutaneous pedicle screw is placed using the C-arm imagery to localize the pedicles on adjacent vertebrae in your spine. Next a skin incision is made and the muscle is pierced by a pedicle probe to the entry point into the pedicle. A wire is passed through the pedicle probe into the vertebral body. The use of the pedicle probe is monitored by a neurologic electrical system to detect any breach of the pedicle that might endanger the passing nerve root. Then a screw is passed over the wire with the neuro-monitoring and C-arm visualization. Once all the screws are placed the connecting rods are passed one by one under the muscle into the tops of the screws and are secured down tightly.

The goal of the percutaneous pedicle screw surgery is to stabilize your spine without damage to the muscular stabilizers of the spine. This allows for a quick recovery of muscle strength and activity. Usually the pedicle screws are placed as a part of a spinal fusion operation. Sometimes the pedicle screws may be placed as a separate procedure, depending on the type of fusion surgery. Risks associated with pedicle screw fixation include misplacement of the pedicle screw related often to tilt and rotation deformity of scoliosis, enlarged facet joints overlying the pedicle, or small or narrow pedicle size. Also screws may break before fusion can occur; wound infection occasionally; and accidental injury to passing nerves may happen. Generally speaking, the chances of experiencing any one of these complications are quite low.